Vacuum system for the removal of pacific converter waste



March 22, 1966 3,241,194

VACUUM SYSTEM FOR THE REMOVAL OF PACIFIC CONVERTER WASTE N. K. SINGLETON Filed May 51, 1963 INVENTOR WILLIAM K. SINGLETON ATTORNEY United States Patent 3,241,194 VACUUM SYSTEM FOR THE REMOVAL OF PACIFIC CONVERTER WASTE William K. Singleton, Camden, S.C., assignor to E. I. du

Pont de Nemours and Company, Wilmington, DeL, a

corporation of Delaware Filed May 31, 1963, Ser. No. 284,661 1 Claim. (Cl. 19-.6)

This invention relates to textile processing of filamentary tows into slivers and more particularly to an improvement in efiiciency of this operation as performed on a Pacific Converter or tow to top machine.

The Pacific Converter is well known in the textile trade as a means for randomly cutting the fibers of a continuous filament tow in such a manner as to permit continuous formation of a staple sliver therefrom. In this process, the fibers are cut between a rotating anvil roll and a spiral cutter, employing very high pressures. This results in the formation of what is termed cutter waste, or snow. This powdery material, consisting of crushed filaments, collects on various parts of the machine and, if not removed periodically, may be picked up by the product sliver and be carried to subsequent steps in textile processing, ultimately adversely aifecting quality of the yarns produced. The need for periodic removal of cutter waste may typically reduce Pacific Converter efiiciency by 6%, and the man power required for removal of waste is nonproductive.

It is an object of this invention to provide automatic means for removal of Pacific Converter waste during continuous operation of the machine.

It is a further object to substantially reduce the nonproductive down-time of a Pacific Converter ordinarily required by the accumulation of cutter waste thereon.

It is a still further object to provide a vacuum means for removing cutter waste from a Pacific Converter as the waste is formed so as to prevent its accumulation on the working parts of the machine by a means which results in no substantial loss of product fiber.

These and other objects are accomplished in this invention by use of vacuum pickup nozzles installed at the anvil roll and over the shuflle sections of the Pacific Converter, said nozzles being of such dimensions and passing air at such a velocity that the powdery cutter waste is removed efficiently without significant loss of cut fiber.

This invention will readily be understood by reference to the drawing which is an over-all schematic perspective view of the Pacific Converter in which the locations of the vacuum nozzles have been indicated.

With reference to the drawing, tow 1 is fed by feed rolls 11, 12 and 13 at a controlled linear speed into the nip of spiral cutter 21 and anvil roll 22. The pieces of cut tow emerging from the cutters are fed directly into debonders 31, 32, 33 and 34 which serve to open the cut pieces, finally depositing them as a loose web in turn, on forwarding belts 45 and 46 which are driven respectively by drive rolls 42 and 43. Shufile rolls 41 rotate at a surface speed substantially higher than that of belts 45 and 46 in the same direction as the forwarding motion of the web on the belts thereby shuttle-drafting the cut fibers in the web. The well-opened and interblended web of fibers from the shuttle section is then fed into the nip of draft rolls 51 which produce the draft by operating at a higher linear speed than belts 45 and 46. The drafted web is deposited on horizontal apron 52 where it is rolled up into a sliver by diagonal roll 61. One end of the rolled sliver is continuously pulled from apron 52 by the feed rolls of stutfing box crimper 71, from which it is fed into sliver can 72 for storage prior to further processing. As the cut tow emerges from the nip of spiral cutter 21 it passes closely beneath vacuum nozzle 23 which picks up the 3,241,194 Patented Mar. 22, 1966 greater portion of the cutter waste which normally either adheres to spiral cutter 21 or remains as a deposit on the cut tow. A further vacuum cleaning is: accomplished over a shufile roll approximately in the center of the shufile roll section by vacuum nozzle 44. Cutter waste which adheres to anvil roll 22 is picked up by vacuum nozzle 24 which is directed against the roll on the emerging side of the nip, just below the newly formed, continuously moving loose web. While it will be apparent that the air velocity which can be used in the processing of any given fiber will vary, depending on the denier of the fiber, the cut length, and the density of the fiber among other factors, it has been found that nozzles 23 and 44 operate satisfactorily if they pick up about 30 cubic feet per minute of air. Nozzle 24, being on the underside of the cut tow, can pick up substantially more, for example, as high as 60 cubic feet per minute, without substantial pick up of cut fiber. All nozzles in this exemplification have an opening 1 inch in width and 16 inches long. In the prior art operation of the process as described, powdery, crushed fiber developed in the nip of the cutter and anvil rolls is picked up by the felts not shown which are held in contact with shuffle rolls 41. At frequent intervals, the process must be interrupted so that these felts can be removed, cleaned of cutter waste, and reinstalled. By the process of this invention, vacuum nozzles 23, 24 and 44 pick up the cutter waste as formed so efi'iciently that machine down time for cleaning of the felts and other operating surfaces may be reduced to a small fraction of normal.

In one direct comparison of amount of cutter waste removed by the prior art method and by the method of this invention, it was found that about twice as much (731 grains vs. 374 grains per pounds of tow processed) was picked up by the vacuum system. The vacuum pickup removed only two grains of longer fiber per 100 pounds of tow processed.

The improved efficiency of pickup is also reflected by the amount of waste carried forward to and deposited on subsequent equipment as is seen by the following table.

It will be obvious to one skilled in the art that the specific details of the embodiment disclosed may be altered materially without departing from the spirit and scope of this invention. Dimensions of and location of the nozzles relative to the cutter or to the anvil rolls and the velocity of air entering the nozzle may be varied widely from the specific disclosure to meet the essential criteria of waste pickup efficiency, low loss of product fiber, and operating economy for any given fiber being processed on this equipment. Such adjustments are most conveniently made in the field, since substantial flexibility in arrangement may easily be built into the apparatus of this invention. It is understood, therefore, that this invention is to be limited only by the claim which follows.

What is claimed is:

In a tow to top yarn processing machine provided with feed rolls, an upper spiral cutter associated with a lower anvil roll to receive in the nip formed by the upper spiral cutter and the lower anvil roll a web of tow emerging from the feed rolls, means for receiving and opening the web of cut tow emerging from said nip, forwarding belts to carry the opened cut tow, and a shuflle roll section associated with the forwarding belts for shuffle-drafting the web of cut tow, the improvement which comprises (1) a vacuum nozzle disposed immediately adjacent to the spiral cutter, substantially along the entire length of the said cutter and immediately above the nip formed by the said cutter with its associated anvil roll and above the said web of cut tow emerging from the said nip whereby cutter waste is removed both from the upper portion of said web of cut tow and said spiral cutter in the vicinity of said nip, (2) a second vacuum nozzle disposed immediately adjacent and above the approximate center roll of the shuffle roll section of the said machine substantially along the entire length of the said center roll and (3) a third vacuum nozzle disposed immediately adjacent to the anvil roll along the entire length of the said roll and immediately below the nip formed by the said anvil roll with its associated cutter and below the said web of cut tow emerging from the said nip whereby cutter waste is removed both from the lower References Cited by the Examiner UNITED STATES PATENTS 2,077,283 4/1937 Taylor et a1 19.62 X 2,438,469 3/1948 Wilkie 19-.6 X 2,719,333 10/1955 Buchanan 19263 X 2,934,797 5/1960 Whitehurst et a1. 19263 X DONALD W. PARKER, Primary Examiner. 

